Optical 3D Metrology (O3DM) is a series of conferences that build on the heritage of SPIE Videometrics (1991-2017) and Optical 3D Measurement Techniques (1989-2009). Renamed as Optical 3D Metrology (O3DM), the past editions were held in Strasbourg (France) in December 2019, in Wuerzburg (Germany) in December 2022 and Brescia (Italy) in 2024 under the umbrella of ISPRS. The 2026 edition will celebrate 35 years of optical metrology workshops!! and the primary theme of O3DM is the precise 3D measurement and accurate modelling from imaging and range sensors.